collision.c

   1
   2 #include "quakedef.h"
   3 #include "polygon.h"
   4
   5 #define COLLISION_EDGEDIR_DOT_EPSILON (0.999f)
   6 #define COLLISION_EDGECROSS_MINLENGTH2 (1.0f / 4194304.0f)
   7 #define COLLISION_SNAPSCALE (32.0f)
   8 #define COLLISION_SNAP (1.0f / COLLISION_SNAPSCALE)
   9 #define COLLISION_SNAP2 (2.0f / COLLISION_SNAPSCALE)
  10 #define COLLISION_PLANE_DIST_EPSILON (2.0f / COLLISION_SNAPSCALE)
  11
  12 cvar_t collision_impactnudge = {0, "collision_impactnudge", "0.03125", "how much to back off from the impact"};
  13 cvar_t collision_startnudge = {0, "collision_startnudge", "0", "how much to bias collision trace start"};
  14 cvar_t collision_endnudge = {0, "collision_endnudge", "0", "how much to bias collision trace end"};
  15 cvar_t collision_enternudge = {0, "collision_enternudge", "0", "how much to bias collision entry fraction"};
  16 cvar_t collision_leavenudge = {0, "collision_leavenudge", "0", "how much to bias collision exit fraction"};
  17 cvar_t collision_extendmovelength = {0, "collision_extendmovelength", "16", "internal bias on trace length to ensure detection of collisions within the collision_impactnudge/collision_enternudge/collision_leavenudge distance so that short moves do not degrade across frames (this does not alter the final trace length)"};
  18 cvar_t collision_extendtraceboxlength = {0, "collision_extendtraceboxlength", "1", "internal bias for tracebox() qc builtin to account for collision_impactnudge/collision_enternudge/collision_leavenudge (this does not alter the final trace length)"};
  19 cvar_t collision_extendtracelinelength = {0, "collision_extendtracelinelength", "1", "internal bias for traceline() qc builtin to account for collision_impactnudge/collision_enternudge/collision_leavenudge (this does not alter the final trace length)"};
  20 cvar_t collision_debug_tracelineasbox = {0, "collision_debug_tracelineasbox", "0", "workaround for any bugs in Collision_TraceLineBrushFloat by using Collision_TraceBrushBrushFloat"};
  21 cvar_t collision_cache = {0, "collision_cache", "1", "store results of collision traces for next frame to reuse if possible (optimization)"};
  22 //cvar_t collision_triangle_neighborsides = {0, "collision_triangle_neighborsides", "1", "override automatic side generation if triangle has neighbors with face planes that form a convex edge (perfect solution, but can not work for all edges)"};
  23 cvar_t collision_triangle_bevelsides = {0, "collision_triangle_bevelsides", "0", "generate sloped edge planes on triangles - if 0, see axialedgeplanes"};
  24 cvar_t collision_triangle_axialsides = {0, "collision_triangle_axialsides", "1", "generate axially-aligned edge planes on triangles - otherwise use perpendicular edge planes"};
  25
  26 mempool_t *collision_mempool;
  27
  28 void Collision_Init (void)
  29 {
  30         Cvar_RegisterVariable(&collision_impactnudge);
  31         Cvar_RegisterVariable(&collision_startnudge);
  32         Cvar_RegisterVariable(&collision_endnudge);
  33         Cvar_RegisterVariable(&collision_enternudge);
  34         Cvar_RegisterVariable(&collision_leavenudge);
  35         Cvar_RegisterVariable(&collision_extendmovelength);
  36         Cvar_RegisterVariable(&collision_extendtracelinelength);
  37         Cvar_RegisterVariable(&collision_extendtraceboxlength);
  38         Cvar_RegisterVariable(&collision_debug_tracelineasbox);
  39         Cvar_RegisterVariable(&collision_cache);
  40 //      Cvar_RegisterVariable(&collision_triangle_neighborsides);
  41         Cvar_RegisterVariable(&collision_triangle_bevelsides);
  42         Cvar_RegisterVariable(&collision_triangle_axialsides);
  43         collision_mempool = Mem_AllocPool("collision cache", 0, NULL);
  44         Collision_Cache_Init(collision_mempool);
  45 }
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60 static void Collision_PrintBrushAsQHull(colbrushf_t *brush, const char *name)
  61 {
  62         int i;
  63         Con_Printf("3 %s\n%i\n", name, brush->numpoints);
  64         for (i = 0;i < brush->numpoints;i++)
  65                 Con_Printf("%f %f %f\n", brush->points[i].v[0], brush->points[i].v[1], brush->points[i].v[2]);
  66         // FIXME: optimize!
  67         Con_Printf("4\n%i\n", brush->numplanes);
  68         for (i = 0;i < brush->numplanes;i++)
  69                 Con_Printf("%f %f %f %f\n", brush->planes[i].normal[0], brush->planes[i].normal[1], brush->planes[i].normal[2], brush->planes[i].dist);
  70 }
  71
  72 static void Collision_ValidateBrush(colbrushf_t *brush)
  73 {
  74         int j, k, pointsoffplanes, pointonplanes, pointswithinsufficientplanes, printbrush;
  75         float d;
  76         printbrush = false;
  77         if (!brush->numpoints)
  78         {
  79                 Con_Print("Collision_ValidateBrush: brush with no points!\n");
  80                 printbrush = true;
  81         }
  82 #if 0
  83         // it's ok for a brush to have one point and no planes...
  84         if (brush->numplanes == 0 && brush->numpoints != 1)
  85         {
  86                 Con_Print("Collision_ValidateBrush: brush with no planes and more than one point!\n");
  87                 printbrush = true;
  88         }
  89 #endif
  90         if (brush->numplanes)
  91         {
  92                 pointsoffplanes = 0;
  93                 pointswithinsufficientplanes = 0;
  94                 for (k = 0;k < brush->numplanes;k++)
  95                         if (DotProduct(brush->planes[k].normal, brush->planes[k].normal) < 0.0001f)
  96                                 Con_Printf("Collision_ValidateBrush: plane #%i (%f %f %f %f) is degenerate\n", k, brush->planes[k].normal[0], brush->planes[k].normal[1], brush->planes[k].normal[2], brush->planes[k].dist);
  97                 for (j = 0;j < brush->numpoints;j++)
  98                 {
  99                         pointonplanes = 0;
 100                         for (k = 0;k < brush->numplanes;k++)
 101                         {
 102                                 d = DotProduct(brush->points[j].v, brush->planes[k].normal) - brush->planes[k].dist;
 103                                 if (d > COLLISION_PLANE_DIST_EPSILON)
 104                                 {
 105                                         Con_Printf("Collision_ValidateBrush: point #%i (%f %f %f) infront of plane #%i (%f %f %f %f)\n", j, brush->points[j].v[0], brush->points[j].v[1], brush->points[j].v[2], k, brush->planes[k].normal[0], brush->planes[k].normal[1], brush->planes[k].normal[2], brush->planes[k].dist);
 106                                         printbrush = true;
 107                                 }
 108                                 if (fabs(d) > COLLISION_PLANE_DIST_EPSILON)
 109                                         pointsoffplanes++;
 110                                 else
 111                                         pointonplanes++;
 112                         }
 113                         if (pointonplanes < 3)
 114                                 pointswithinsufficientplanes++;
 115                 }
 116                 if (pointswithinsufficientplanes)
 117                 {
 118                         Con_Print("Collision_ValidateBrush: some points have insufficient planes, every point must be on at least 3 planes to form a corner.\n");
 119                         printbrush = true;
 120                 }
 121                 if (pointsoffplanes == 0) // all points are on all planes
 122                 {
 123                         Con_Print("Collision_ValidateBrush: all points lie on all planes (degenerate, no brush volume!)\n");
 124                         printbrush = true;
 125                 }
 126         }
 127         if (printbrush)
 128                 Collision_PrintBrushAsQHull(brush, "unnamed");
 129 }
 130
 131 static float nearestplanedist_float(const float *normal, const colpointf_t *points, int numpoints)
 132 {
 133         float dist, bestdist;
 134         if (!numpoints)
 135                 return 0;
 136         bestdist = DotProduct(points->v, normal);
 137         points++;
 138         while(--numpoints)
 139         {
 140                 dist = DotProduct(points->v, normal);
 141                 bestdist = min(bestdist, dist);
 142                 points++;
 143         }
 144         return bestdist;
 145 }
 146
 147 static float furthestplanedist_float(const float *normal, const colpointf_t *points, int numpoints)
 148 {
 149         float dist, bestdist;
 150         if (!numpoints)
 151                 return 0;
 152         bestdist = DotProduct(points->v, normal);
 153         points++;
 154         while(--numpoints)
 155         {
 156                 dist = DotProduct(points->v, normal);
 157                 bestdist = max(bestdist, dist);
 158                 points++;
 159         }
 160         return bestdist;
 161 }
 162
 163 static void Collision_CalcEdgeDirsForPolygonBrushFloat(colbrushf_t *brush)
 164 {
 165         int i, j;
 166         for (i = 0, j = brush->numpoints - 1;i < brush->numpoints;j = i, i++)
 167                 VectorSubtract(brush->points[i].v, brush->points[j].v, brush->edgedirs[j].v);
 168 }
 169
 170 colbrushf_t *Collision_NewBrushFromPlanes(mempool_t *mempool, int numoriginalplanes, const colplanef_t *originalplanes, int supercontents, int q3surfaceflags, const texture_t *texture, int hasaabbplanes)
 171 {
 172         // TODO: planesbuf could be replaced by a remapping table
 173         int j, k, l, m, w, xyzflags;
 174         int numpointsbuf = 0, maxpointsbuf = 256, numedgedirsbuf = 0, maxedgedirsbuf = 256, numplanesbuf = 0, maxplanesbuf = 256, numelementsbuf = 0, maxelementsbuf = 256;
 175         int isaabb = true;
 176         double maxdist;
 177         colbrushf_t *brush;
 178         colpointf_t pointsbuf[256];
 179         colpointf_t edgedirsbuf[256];
 180         colplanef_t planesbuf[256];
 181         int elementsbuf[1024];
 182         int polypointbuf[256];
 183         int pmaxpoints = 64;
 184         int pnumpoints;
 185         double p[2][3*64];
 186 #if 0
 187         // enable these if debugging to avoid seeing garbage in unused data-
 188         memset(pointsbuf, 0, sizeof(pointsbuf));
 189         memset(edgedirsbuf, 0, sizeof(edgedirsbuf));
 190         memset(planesbuf, 0, sizeof(planesbuf));
 191         memset(elementsbuf, 0, sizeof(elementsbuf));
 192         memset(polypointbuf, 0, sizeof(polypointbuf));
 193         memset(p, 0, sizeof(p));
 194 #endif
 195
 196         // check if there are too many planes and skip the brush
 197         if (numoriginalplanes >= maxplanesbuf)
 198         {
 199                 Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many planes for buffer\n");
 200                 return NULL;
 201         }
 202
 203         // figure out how large a bounding box we need to properly compute this brush
 204         maxdist = 0;
 205         for (j = 0;j < numoriginalplanes;j++)
 206                 maxdist = max(maxdist, fabs(originalplanes[j].dist));
 207         // now make it large enough to enclose the entire brush, and round it off to a reasonable multiple of 1024
 208         maxdist = floor(maxdist * (4.0 / 1024.0) + 2) * 1024.0;
 209         // construct a collision brush (points, planes, and renderable mesh) from
 210         // a set of planes, this also optimizes out any unnecessary planes (ones
 211         // whose polygon is clipped away by the other planes)
 212         for (j = 0;j < numoriginalplanes;j++)
 213         {
 214                 // add the new plane
 215                 VectorCopy(originalplanes[j].normal, planesbuf[numplanesbuf].normal);
 216                 planesbuf[numplanesbuf].dist = originalplanes[j].dist;
 217                 planesbuf[numplanesbuf].q3surfaceflags = originalplanes[j].q3surfaceflags;
 218                 planesbuf[numplanesbuf].texture = originalplanes[j].texture;
 219                 numplanesbuf++;
 220
 221                 // create a large polygon from the plane
 222                 w = 0;
 223                 PolygonD_QuadForPlane(p[w], originalplanes[j].normal[0], originalplanes[j].normal[1], originalplanes[j].normal[2], originalplanes[j].dist, maxdist);
 224                 pnumpoints = 4;
 225                 // clip it by all other planes
 226                 for (k = 0;k < numoriginalplanes && pnumpoints >= 3 && pnumpoints <= pmaxpoints;k++)
 227                 {
 228                         // skip the plane this polygon
 229                         // (nothing happens if it is processed, this is just an optimization)
 230                         if (k != j)
 231                         {
 232                                 // we want to keep the inside of the brush plane so we flip
 233                                 // the cutting plane
 234                                 PolygonD_Divide(pnumpoints, p[w], -originalplanes[k].normal[0], -originalplanes[k].normal[1], -originalplanes[k].normal[2], -originalplanes[k].dist, COLLISION_PLANE_DIST_EPSILON, pmaxpoints, p[!w], &pnumpoints, 0, NULL, NULL, NULL);
 235                                 w = !w;
 236                         }
 237                 }
 238
 239                 // if nothing is left, skip it
 240                 if (pnumpoints < 3)
 241                 {
 242                         //Con_DPrintf("Collision_NewBrushFromPlanes: warning: polygon for plane %f %f %f %f clipped away\n", originalplanes[j].normal[0], originalplanes[j].normal[1], originalplanes[j].normal[2], originalplanes[j].dist);
 243                         continue;
 244                 }
 245
 246                 for (k = 0;k < pnumpoints;k++)
 247                 {
 248                         int l, m;
 249                         m = 0;
 250                         for (l = 0;l < numoriginalplanes;l++)
 251                                 if (fabs(DotProduct(&p[w][k*3], originalplanes[l].normal) - originalplanes[l].dist) < COLLISION_PLANE_DIST_EPSILON)
 252                                         m++;
 253                         if (m < 3)
 254                                 break;
 255                 }
 256                 if (k < pnumpoints)
 257                 {
 258                         Con_DPrintf("Collision_NewBrushFromPlanes: warning: polygon point does not lie on at least 3 planes\n");
 259                         //return NULL;
 260                 }
 261
 262                 // check if there are too many polygon vertices for buffer
 263                 if (pnumpoints > pmaxpoints)
 264                 {
 265                         Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many points for buffer\n");
 266                         return NULL;
 267                 }
 268
 269                 // check if there are too many triangle elements for buffer
 270                 if (numelementsbuf + (pnumpoints - 2) * 3 > maxelementsbuf)
 271                 {
 272                         Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many triangle elements for buffer\n");
 273                         return NULL;
 274                 }
 275
 276                 // add the unique points for this polygon
 277                 for (k = 0;k < pnumpoints;k++)
 278                 {
 279                         float v[3];
 280                         // downgrade to float precision before comparing
 281                         VectorCopy(&p[w][k*3], v);
 282
 283                         // check if there is already a matching point (no duplicates)
 284                         for (m = 0;m < numpointsbuf;m++)
 285                                 if (VectorDistance2(v, pointsbuf[m].v) < COLLISION_SNAP2)
 286                                         break;
 287
 288                         // if there is no match, add a new one
 289                         if (m == numpointsbuf)
 290                         {
 291                                 // check if there are too many and skip the brush
 292                                 if (numpointsbuf >= maxpointsbuf)
 293                                 {
 294                                         Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many points for buffer\n");
 295                                         return NULL;
 296                                 }
 297                                 // add the new one
 298                                 VectorCopy(&p[w][k*3], pointsbuf[numpointsbuf].v);
 299                                 numpointsbuf++;
 300                         }
 301
 302                         // store the index into a buffer
 303                         polypointbuf[k] = m;
 304                 }
 305
 306                 // add the triangles for the polygon
 307                 // (this particular code makes a triangle fan)
 308                 for (k = 0;k < pnumpoints - 2;k++)
 309                 {
 310                         elementsbuf[numelementsbuf++] = polypointbuf[0];
 311                         elementsbuf[numelementsbuf++] = polypointbuf[k + 1];
 312                         elementsbuf[numelementsbuf++] = polypointbuf[k + 2];
 313                 }
 314
 315                 // add the unique edgedirs for this polygon
 316                 for (k = 0, l = pnumpoints-1;k < pnumpoints;l = k, k++)
 317                 {
 318                         float dir[3];
 319                         // downgrade to float precision before comparing
 320                         VectorSubtract(&p[w][k*3], &p[w][l*3], dir);
 321                         VectorNormalize(dir);
 322
 323                         // check if there is already a matching edgedir (no duplicates)
 324                         for (m = 0;m < numedgedirsbuf;m++)
 325                                 if (DotProduct(dir, edgedirsbuf[m].v) >= COLLISION_EDGEDIR_DOT_EPSILON)
 326                                         break;
 327                         // skip this if there is
 328                         if (m < numedgedirsbuf)
 329                                 continue;
 330
 331                         // try again with negated edgedir
 332                         VectorNegate(dir, dir);
 333                         // check if there is already a matching edgedir (no duplicates)
 334                         for (m = 0;m < numedgedirsbuf;m++)
 335                                 if (DotProduct(dir, edgedirsbuf[m].v) >= COLLISION_EDGEDIR_DOT_EPSILON)
 336                                         break;
 337                         // if there is no match, add a new one
 338                         if (m == numedgedirsbuf)
 339                         {
 340                                 // check if there are too many and skip the brush
 341                                 if (numedgedirsbuf >= maxedgedirsbuf)
 342                                 {
 343                                         Con_DPrint("Collision_NewBrushFromPlanes: failed to build collision brush: too many edgedirs for buffer\n");
 344                                         return NULL;
 345                                 }
 346                                 // add the new one
 347                                 VectorCopy(dir, edgedirsbuf[numedgedirsbuf].v);
 348                                 numedgedirsbuf++;
 349                         }
 350                 }
 351
 352                 // if any normal is not purely axial, it's not an axis-aligned box
 353                 if (isaabb && (originalplanes[j].normal[0] == 0) + (originalplanes[j].normal[1] == 0) + (originalplanes[j].normal[2] == 0) < 2)
 354                         isaabb = false;
 355         }
 356
 357         // if nothing is left, there's nothing to allocate
 358         if (numplanesbuf < 4)
 359         {
 360                 Con_DPrintf("Collision_NewBrushFromPlanes: failed to build collision brush: %i triangles, %i planes (input was %i planes), %i vertices\n", numelementsbuf / 3, numplanesbuf, numoriginalplanes, numpointsbuf);
 361                 return NULL;
 362         }
 363
 364         // if no triangles or points could be constructed, then this routine failed but the brush is not discarded
 365         if (numelementsbuf < 12 || numpointsbuf < 4)
 366                 Con_DPrintf("Collision_NewBrushFromPlanes: unable to rebuild triangles/points for collision brush: %i triangles, %i planes (input was %i planes), %i vertices\n", numelementsbuf / 3, numplanesbuf, numoriginalplanes, numpointsbuf);
 367
 368         // validate plane distances
 369         for (j = 0;j < numplanesbuf;j++)
 370         {
 371                 float d = furthestplanedist_float(planesbuf[j].normal, pointsbuf, numpointsbuf);
 372                 if (fabs(planesbuf[j].dist - d) > COLLISION_PLANE_DIST_EPSILON)
 373                         Con_DPrintf("plane %f %f %f %f mismatches dist %f\n", planesbuf[j].normal[0], planesbuf[j].normal[1], planesbuf[j].normal[2], planesbuf[j].dist, d);
 374         }
 375
 376         // allocate the brush and copy to it
 377         brush = (colbrushf_t *)Mem_Alloc(mempool, sizeof(colbrushf_t) + sizeof(colpointf_t) * numpointsbuf + sizeof(colpointf_t) * numedgedirsbuf + sizeof(colplanef_t) * numplanesbuf + sizeof(int) * numelementsbuf);
 378         brush->isaabb = isaabb;
 379         brush->hasaabbplanes = hasaabbplanes;
 380         brush->supercontents = supercontents;
 381         brush->numplanes = numplanesbuf;
 382         brush->numedgedirs = numedgedirsbuf;
 383         brush->numpoints = numpointsbuf;
 384         brush->numtriangles = numelementsbuf / 3;
 385         brush->planes = (colplanef_t *)(brush + 1);
 386         brush->points = (colpointf_t *)(brush->planes + brush->numplanes);
 387         brush->edgedirs = (colpointf_t *)(brush->points + brush->numpoints);
 388         brush->elements = (int *)(brush->points + brush->numpoints);
 389         brush->q3surfaceflags = q3surfaceflags;
 390         brush->texture = texture;
 391         for (j = 0;j < brush->numpoints;j++)
 392         {
 393                 brush->points[j].v[0] = pointsbuf[j].v[0];
 394                 brush->points[j].v[1] = pointsbuf[j].v[1];
 395                 brush->points[j].v[2] = pointsbuf[j].v[2];
 396         }
 397         for (j = 0;j < brush->numedgedirs;j++)
 398         {
 399                 brush->edgedirs[j].v[0] = edgedirsbuf[j].v[0];
 400                 brush->edgedirs[j].v[1] = edgedirsbuf[j].v[1];
 401                 brush->edgedirs[j].v[2] = edgedirsbuf[j].v[2];
 402         }
 403         for (j = 0;j < brush->numplanes;j++)
 404         {
 405                 brush->planes[j].normal[0] = planesbuf[j].normal[0];
 406                 brush->planes[j].normal[1] = planesbuf[j].normal[1];
 407                 brush->planes[j].normal[2] = planesbuf[j].normal[2];
 408                 brush->planes[j].dist = planesbuf[j].dist;
 409                 brush->planes[j].q3surfaceflags = planesbuf[j].q3surfaceflags;
 410                 brush->planes[j].texture = planesbuf[j].texture;
 411         }
 412         for (j = 0;j < brush->numtriangles * 3;j++)
 413                 brush->elements[j] = elementsbuf[j];
 414
 415         xyzflags = 0;
 416         VectorClear(brush->mins);
 417         VectorClear(brush->maxs);
 418         for (j = 0;j < min(6, numoriginalplanes);j++)
 419         {
 420                      if (originalplanes[j].normal[0] ==  1) {xyzflags |=  1;brush->maxs[0] =  originalplanes[j].dist;}
 421                 else if (originalplanes[j].normal[0] == -1) {xyzflags |=  2;brush->mins[0] = -originalplanes[j].dist;}
 422                 else if (originalplanes[j].normal[1] ==  1) {xyzflags |=  4;brush->maxs[1] =  originalplanes[j].dist;}
 423                 else if (originalplanes[j].normal[1] == -1) {xyzflags |=  8;brush->mins[1] = -originalplanes[j].dist;}
 424                 else if (originalplanes[j].normal[2] ==  1) {xyzflags |= 16;brush->maxs[2] =  originalplanes[j].dist;}
 425                 else if (originalplanes[j].normal[2] == -1) {xyzflags |= 32;brush->mins[2] = -originalplanes[j].dist;}
 426         }
 427         // if not all xyzflags were set, then this is not a brush from q3map/q3map2, and needs reconstruction of the bounding box
 428         // (this case works for any brush with valid points, but sometimes brushes are not reconstructed properly and hence the points are not valid, so this is reserved as a fallback case)
 429         if (xyzflags != 63)
 430         {
 431                 VectorCopy(brush->points[0].v, brush->mins);
 432                 VectorCopy(brush->points[0].v, brush->maxs);
 433                 for (j = 1;j < brush->numpoints;j++)
 434                 {
 435                         brush->mins[0] = min(brush->mins[0], brush->points[j].v[0]);
 436                         brush->mins[1] = min(brush->mins[1], brush->points[j].v[1]);
 437                         brush->mins[2] = min(brush->mins[2], brush->points[j].v[2]);
 438                         brush->maxs[0] = max(brush->maxs[0], brush->points[j].v[0]);
 439                         brush->maxs[1] = max(brush->maxs[1], brush->points[j].v[1]);
 440                         brush->maxs[2] = max(brush->maxs[2], brush->points[j].v[2]);
 441                 }
 442         }
 443         brush->mins[0] -= 1;
 444         brush->mins[1] -= 1;
 445         brush->mins[2] -= 1;
 446         brush->maxs[0] += 1;
 447         brush->maxs[1] += 1;
 448         brush->maxs[2] += 1;
 449         Collision_ValidateBrush(brush);
 450         return brush;
 451 }
 452
 453
 454
 455 void Collision_CalcPlanesForTriangleBrushFloat(colbrushf_t *brush)
 456 {
 457         int i;
 458         float edge0[3], edge1[3], edge2[3];
 459         colpointf_t *p;
 460
 461         TriangleNormal(brush->points[0].v, brush->points[1].v, brush->points[2].v, brush->planes[0].normal);
 462         if (DotProduct(brush->planes[0].normal, brush->planes[0].normal) < 0.0001f)
 463         {
 464                 // there's no point in processing a degenerate triangle (GIGO - Garbage In, Garbage Out)
 465                 // note that some of these exist in q3bsp bspline patches
 466                 brush->numplanes = 0;
 467                 return;
 468         }
 469
 470         // there are 5 planes (front, back, sides) and 3 edges
 471         brush->numplanes = 5;
 472         brush->numedgedirs = 3;
 473         VectorNormalize(brush->planes[0].normal);
 474         brush->planes[0].dist = DotProduct(brush->points->v, brush->planes[0].normal);
 475         VectorNegate(brush->planes[0].normal, brush->planes[1].normal);
 476         brush->planes[1].dist = -brush->planes[0].dist;
 477         // edge directions are easy to calculate
 478         VectorSubtract(brush->points[2].v, brush->points[0].v, edge0);
 479         VectorSubtract(brush->points[0].v, brush->points[1].v, edge1);
 480         VectorSubtract(brush->points[1].v, brush->points[2].v, edge2);
 481         VectorCopy(edge0, brush->edgedirs[0].v);
 482         VectorCopy(edge1, brush->edgedirs[1].v);
 483         VectorCopy(edge2, brush->edgedirs[2].v);
 484         // now select an algorithm to generate the side planes
 485         if (collision_triangle_bevelsides.integer)
 486         {
 487                 // use 45 degree slopes at the edges of the triangle to make a sinking trace error turn into "riding up" the slope rather than getting stuck
 488                 CrossProduct(edge0, brush->planes->normal, brush->planes[2].normal);
 489                 CrossProduct(edge1, brush->planes->normal, brush->planes[3].normal);
 490                 CrossProduct(edge2, brush->planes->normal, brush->planes[4].normal);
 491                 VectorNormalize(brush->planes[2].normal);
 492                 VectorNormalize(brush->planes[3].normal);
 493                 VectorNormalize(brush->planes[4].normal);
 494                 VectorAdd(brush->planes[2].normal, brush->planes[0].normal, brush->planes[2].normal);
 495                 VectorAdd(brush->planes[3].normal, brush->planes[0].normal, brush->planes[3].normal);
 496                 VectorAdd(brush->planes[4].normal, brush->planes[0].normal, brush->planes[4].normal);
 497                 VectorNormalize(brush->planes[2].normal);
 498                 VectorNormalize(brush->planes[3].normal);
 499                 VectorNormalize(brush->planes[4].normal);
 500         }
 501         else if (collision_triangle_axialsides.integer)
 502         {
 503                 float projectionnormal[3], projectionedge0[3], projectionedge1[3], projectionedge2[3];
 504                 int i, best;
 505                 float dist, bestdist;
 506                 bestdist = fabs(brush->planes[0].normal[0]);
 507                 best = 0;
 508                 for (i = 1;i < 3;i++)
 509                 {
 510                         dist = fabs(brush->planes[0].normal[i]);
 511                         if (bestdist < dist)
 512                         {
 513                                 bestdist = dist;
 514                                 best = i;
 515                         }
 516                 }
 517                 VectorClear(projectionnormal);
 518                 if (brush->planes[0].normal[best] < 0)
 519                         projectionnormal[best] = -1;
 520                 else
 521                         projectionnormal[best] = 1;
 522                 VectorCopy(edge0, projectionedge0);
 523                 VectorCopy(edge1, projectionedge1);
 524                 VectorCopy(edge2, projectionedge2);
 525                 projectionedge0[best] = 0;
 526                 projectionedge1[best] = 0;
 527                 projectionedge2[best] = 0;
 528                 CrossProduct(projectionedge0, projectionnormal, brush->planes[2].normal);
 529                 CrossProduct(projectionedge1, projectionnormal, brush->planes[3].normal);
 530                 CrossProduct(projectionedge2, projectionnormal, brush->planes[4].normal);
 531                 VectorNormalize(brush->planes[2].normal);
 532                 VectorNormalize(brush->planes[3].normal);
 533                 VectorNormalize(brush->planes[4].normal);
 534         }
 535         else
 536         {
 537                 CrossProduct(edge0, brush->planes->normal, brush->planes[2].normal);
 538                 CrossProduct(edge1, brush->planes->normal, brush->planes[3].normal);
 539                 CrossProduct(edge2, brush->planes->normal, brush->planes[4].normal);
 540                 VectorNormalize(brush->planes[2].normal);
 541                 VectorNormalize(brush->planes[3].normal);
 542                 VectorNormalize(brush->planes[4].normal);
 543         }
 544         brush->planes[2].dist = DotProduct(brush->points[2].v, brush->planes[2].normal);
 545         brush->planes[3].dist = DotProduct(brush->points[0].v, brush->planes[3].normal);
 546         brush->planes[4].dist = DotProduct(brush->points[1].v, brush->planes[4].normal);
 547
 548         if (developer_extra.integer)
 549         {
 550                 // validity check - will be disabled later
 551                 Collision_ValidateBrush(brush);
 552                 for (i = 0;i < brush->numplanes;i++)
 553                 {
 554                         int j;
 555                         for (j = 0, p = brush->points;j < brush->numpoints;j++, p++)
 556                                 if (DotProduct(p->v, brush->planes[i].normal) > brush->planes[i].dist + COLLISION_PLANE_DIST_EPSILON)
 557                                         Con_DPrintf("Error in brush plane generation, plane %i\n", i);
 558                 }
 559         }
 560 }
 561
 562 colbrushf_t *Collision_AllocBrushFromPermanentPolygonFloat(mempool_t *mempool, int numpoints, float *points, int supercontents, int q3surfaceflags, const texture_t *texture)
 563 {
 564         colbrushf_t *brush;
 565         brush = (colbrushf_t *)Mem_Alloc(mempool, sizeof(colbrushf_t) + sizeof(colplanef_t) * (numpoints + 2) + sizeof(colpointf_t) * numpoints);
 566         brush->isaabb = false;
 567         brush->hasaabbplanes = false;
 568         brush->supercontents = supercontents;
 569         brush->numpoints = numpoints;
 570         brush->numedgedirs = numpoints;
 571         brush->numplanes = numpoints + 2;
 572         brush->planes = (colplanef_t *)(brush + 1);
 573         brush->points = (colpointf_t *)points;
 574         brush->edgedirs = (colpointf_t *)(brush->planes + brush->numplanes);
 575         brush->q3surfaceflags = q3surfaceflags;
 576         brush->texture = texture;
 577         Sys_Error("Collision_AllocBrushFromPermanentPolygonFloat: FIXME: this code needs to be updated to generate a mesh...");
 578         return brush;
 579 }
 580
 581 // NOTE: start and end of each brush pair must have same numplanes/numpoints
 582 void Collision_TraceBrushBrushFloat(trace_t *trace, const colbrushf_t *trace_start, const colbrushf_t *trace_end, const colbrushf_t *other_start, const colbrushf_t *other_end)
 583 {
 584         int nplane, nplane2, nedge1, nedge2, hitq3surfaceflags = 0;
 585         int tracenumedgedirs = trace_start->numedgedirs;
 586         //int othernumedgedirs = other_start->numedgedirs;
 587         int tracenumpoints = trace_start->numpoints;
 588         int othernumpoints = other_start->numpoints;
 589         int numplanes1 = other_start->numplanes;
 590         int numplanes2 = numplanes1 + trace_start->numplanes;
 591         int numplanes3 = numplanes2 + trace_start->numedgedirs * other_start->numedgedirs * 2;
 592         vec_t enterfrac = -1, leavefrac = 1, startdist, enddist, ie, f, imove, enterfrac2 = -1;
 593         vec4_t startplane;
 594         vec4_t endplane;
 595         vec4_t newimpactplane;
 596         const texture_t *hittexture = NULL;
 597         vec_t startdepth = 1;
 598         vec3_t startdepthnormal;
 599
 600         VectorClear(startdepthnormal);
 601         Vector4Clear(newimpactplane);
 602
 603         // fast case for AABB vs compiled brushes (which begin with AABB planes and also have precomputed bevels for AABB collisions)
 604         if (trace_start->isaabb && other_start->hasaabbplanes)
 605                 numplanes3 = numplanes2 = numplanes1;
 606
 607         // Separating Axis Theorem:
 608         // if a supporting vector (plane normal) can be found that separates two
 609         // objects, they are not colliding.
 610         //
 611         // Minkowski Sum:
 612         // reduce the size of one object to a point while enlarging the other to
 613         // represent the space that point can not occupy.
 614         //
 615         // try every plane we can construct between the two brushes and measure
 616         // the distance between them.
 617         for (nplane = 0;nplane < numplanes3;nplane++)
 618         {
 619                 if (nplane < numplanes1)
 620                 {
 621                         nplane2 = nplane;
 622                         VectorCopy(other_start->planes[nplane2].normal, startplane);
 623                         VectorCopy(other_end->planes[nplane2].normal, endplane);
 624                 }
 625                 else if (nplane < numplanes2)
 626                 {
 627                         nplane2 = nplane - numplanes1;
 628                         VectorCopy(trace_start->planes[nplane2].normal, startplane);
 629                         VectorCopy(trace_end->planes[nplane2].normal, endplane);
 630                 }
 631                 else
 632                 {
 633                         // pick an edgedir from each brush and cross them
 634                         nplane2 = nplane - numplanes2;
 635                         nedge1 = nplane2 >> 1;
 636                         nedge2 = nedge1 / tracenumedgedirs;
 637                         nedge1 -= nedge2 * tracenumedgedirs;
 638                         if (nplane2 & 1)
 639                         {
 640                                 CrossProduct(trace_start->edgedirs[nedge1].v, other_start->edgedirs[nedge2].v, startplane);
 641                                 CrossProduct(trace_end->edgedirs[nedge1].v, other_end->edgedirs[nedge2].v, endplane);
 642                         }
 643                         else
 644                         {
 645                                 CrossProduct(other_start->edgedirs[nedge2].v, trace_start->edgedirs[nedge1].v, startplane);
 646                                 CrossProduct(other_end->edgedirs[nedge2].v, trace_end->edgedirs[nedge1].v, endplane);
 647                         }
 648                         if (VectorLength2(startplane) < COLLISION_EDGECROSS_MINLENGTH2 || VectorLength2(endplane) < COLLISION_EDGECROSS_MINLENGTH2)
 649                                 continue; // degenerate crossproducts
 650                         VectorNormalize(startplane);
 651                         VectorNormalize(endplane);
 652                 }
 653                 startplane[3] = furthestplanedist_float(startplane, other_start->points, othernumpoints);
 654                 endplane[3] = furthestplanedist_float(startplane, other_end->points, othernumpoints);
 655                 startdist = nearestplanedist_float(startplane, trace_start->points, tracenumpoints) - startplane[3] - collision_startnudge.value;
 656                 enddist = nearestplanedist_float(endplane, trace_end->points, tracenumpoints) - endplane[3] - collision_endnudge.value;
 657                 //Con_Printf("%c%i: startdist = %f, enddist = %f, startdist / (startdist - enddist) = %f\n", nplane2 != nplane ? 'b' : 'a', nplane2, startdist, enddist, startdist / (startdist - enddist));
 658
 659                 // aside from collisions, this is also used for error correction
 660                 if (startdist <= collision_impactnudge.value && nplane < numplanes1 && (startdepth < startdist || startdepth == 1))
 661                 {
 662                         startdepth = startdist;
 663                         VectorCopy(startplane, startdepthnormal);
 664                 }
 665
 666                 if (startdist > enddist)
 667                 {
 668                         // moving into brush
 669                         if (enddist >= collision_enternudge.value)
 670                                 return;
 671                         if (startdist >= 0)
 672                         {
 673                                 // enter
 674                                 imove = 1 / (startdist - enddist);
 675                                 f = (startdist - collision_enternudge.value) * imove;
 676                                 if (f < 0)
 677                                         f = 0;
 678                                 // check if this will reduce the collision time range
 679                                 if (enterfrac < f)
 680                                 {
 681                                         // reduced collision time range
 682                                         enterfrac = f;
 683                                         // if the collision time range is now empty, no collision
 684                                         if (enterfrac > leavefrac)
 685                                                 return;
 686                                         // calculate the nudged fraction and impact normal we'll
 687                                         // need if we accept this collision later
 688                                         enterfrac2 = (startdist - collision_impactnudge.value) * imove;
 689                                         // if the collision would be further away than the trace's
 690                                         // existing collision data, we don't care about this
 691                                         // collision
 692                                         if (enterfrac2 >= trace->fraction)
 693                                                 return;
 694                                         ie = 1.0f - enterfrac;
 695                                         newimpactplane[0] = startplane[0] * ie + endplane[0] * enterfrac;
 696                                         newimpactplane[1] = startplane[1] * ie + endplane[1] * enterfrac;
 697                                         newimpactplane[2] = startplane[2] * ie + endplane[2] * enterfrac;
 698                                         newimpactplane[3] = startplane[3] * ie + endplane[3] * enterfrac;
 699                                         if (nplane < numplanes1)
 700                                         {
 701                                                 // use the plane from other
 702                                                 nplane2 = nplane;
 703                                                 hitq3surfaceflags = other_start->planes[nplane2].q3surfaceflags;
 704                                                 hittexture = other_start->planes[nplane2].texture;
 705                                         }
 706                                         else if (nplane < numplanes2)
 707                                         {
 708                                                 // use the plane from trace
 709                                                 nplane2 = nplane - numplanes1;
 710                                                 hitq3surfaceflags = trace_start->planes[nplane2].q3surfaceflags;
 711                                                 hittexture = trace_start->planes[nplane2].texture;
 712                                         }
 713                                         else
 714                                         {
 715                                                 hitq3surfaceflags = other_start->q3surfaceflags;
 716                                                 hittexture = other_start->texture;
 717                                         }
 718                                 }
 719                         }
 720                 }
 721                 else
 722                 {
 723                         // moving out of brush
 724                         if (startdist >= 0)
 725                                 return;
 726                         if (enddist > 0)
 727                         {
 728                                 // leave
 729                                 f = (startdist + collision_leavenudge.value) / (startdist - enddist);
 730                                 if (f > 1)
 731                                         f = 1;
 732                                 // check if this will reduce the collision time range
 733                                 if (leavefrac > f)
 734                                 {
 735                                         // reduced collision time range
 736                                         leavefrac = f;
 737                                         // if the collision time range is now empty, no collision
 738                                         if (enterfrac > leavefrac)
 739                                                 return;
 740                                 }
 741                         }
 742                 }
 743         }
 744
 745         // at this point we know the trace overlaps the brush because it was not
 746         // rejected at any point in the loop above
 747
 748         // see if the trace started outside the brush or not
 749         if (enterfrac > -1)
 750         {
 751                 // started outside, and overlaps, therefore there is a collision here
 752                 // store out the impact information
 753                 if (trace->hitsupercontentsmask & other_start->supercontents)
 754                 {
 755                         trace->hitsupercontents = other_start->supercontents;
 756                         trace->hitq3surfaceflags = hitq3surfaceflags;
 757                         trace->hittexture = hittexture;
 758                         trace->fraction = bound(0, enterfrac2, 1);
 759                         VectorCopy(newimpactplane, trace->plane.normal);
 760                         trace->plane.dist = newimpactplane[3];
 761                 }
 762         }
 763         else
 764         {
 765                 // started inside, update startsolid and friends
 766                 trace->startsupercontents |= other_start->supercontents;
 767                 if (trace->hitsupercontentsmask & other_start->supercontents)
 768                 {
 769                         trace->startsolid = true;
 770                         if (leavefrac < 1)
 771                                 trace->allsolid = true;
 772                         VectorCopy(newimpactplane, trace->plane.normal);
 773                         trace->plane.dist = newimpactplane[3];
 774                         if (trace->startdepth > startdepth)
 775                         {
 776                                 trace->startdepth = startdepth;
 777                                 VectorCopy(startdepthnormal, trace->startdepthnormal);
 778                         }
 779                 }
 780         }
 781 }
 782
 783 // NOTE: start and end of each brush pair must have same numplanes/numpoints
 784 void Collision_TraceLineBrushFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, const colbrushf_t *other_start, const colbrushf_t *other_end)
 785 {
 786         int nplane, hitq3surfaceflags = 0;
 787         int numplanes = other_start->numplanes;
 788         vec_t enterfrac = -1, leavefrac = 1, startdist, enddist, ie, f, imove, enterfrac2 = -1;
 789         vec4_t startplane;
 790         vec4_t endplane;
 791         vec4_t newimpactplane;
 792         const texture_t *hittexture = NULL;
 793         vec_t startdepth = 1;
 794         vec3_t startdepthnormal;
 795
 796         if (collision_debug_tracelineasbox.integer)
 797         {
 798                 colboxbrushf_t thisbrush_start, thisbrush_end;
 799                 Collision_BrushForBox(&thisbrush_start, linestart, linestart, 0, 0, NULL);
 800                 Collision_BrushForBox(&thisbrush_end, lineend, lineend, 0, 0, NULL);
 801                 Collision_TraceBrushBrushFloat(trace, &thisbrush_start.brush, &thisbrush_end.brush, other_start, other_end);
 802                 return;
 803         }
 804
 805         VectorClear(startdepthnormal);
 806         Vector4Clear(newimpactplane);
 807
 808         // Separating Axis Theorem:
 809         // if a supporting vector (plane normal) can be found that separates two
 810         // objects, they are not colliding.
 811         //
 812         // Minkowski Sum:
 813         // reduce the size of one object to a point while enlarging the other to
 814         // represent the space that point can not occupy.
 815         //
 816         // try every plane we can construct between the two brushes and measure
 817         // the distance between them.
 818         for (nplane = 0;nplane < numplanes;nplane++)
 819         {
 820                 VectorCopy(other_start->planes[nplane].normal, startplane);
 821                 startplane[3] = other_start->planes[nplane].dist;
 822                 VectorCopy(other_end->planes[nplane].normal, endplane);
 823                 endplane[3] = other_end->planes[nplane].dist;
 824                 startdist = DotProduct(linestart, startplane) - startplane[3] - collision_startnudge.value;
 825                 enddist = DotProduct(lineend, endplane) - endplane[3] - collision_endnudge.value;
 826                 //Con_Printf("%c%i: startdist = %f, enddist = %f, startdist / (startdist - enddist) = %f\n", nplane2 != nplane ? 'b' : 'a', nplane2, startdist, enddist, startdist / (startdist - enddist));
 827
 828                 // aside from collisions, this is also used for error correction
 829                 if (startdist < collision_impactnudge.value && (startdepth < startdist || startdepth == 1))
 830                 {
 831                         startdepth = startdist;
 832                         VectorCopy(startplane, startdepthnormal);
 833                 }
 834
 835                 if (startdist > enddist)
 836                 {
 837                         // moving into brush
 838                         if (enddist >= collision_enternudge.value)
 839                                 return;
 840                         if (startdist > 0)
 841                         {
 842                                 // enter
 843                                 imove = 1 / (startdist - enddist);
 844                                 f = (startdist - collision_enternudge.value) * imove;
 845                                 if (f < 0)
 846                                         f = 0;
 847                                 // check if this will reduce the collision time range
 848                                 if (enterfrac < f)
 849                                 {
 850                                         // reduced collision time range
 851                                         enterfrac = f;
 852                                         // if the collision time range is now empty, no collision
 853                                         if (enterfrac > leavefrac)
 854                                                 return;
 855                                         // calculate the nudged fraction and impact normal we'll
 856                                         // need if we accept this collision later
 857                                         enterfrac2 = (startdist - collision_impactnudge.value) * imove;
 858                                         // if the collision would be further away than the trace's
 859                                         // existing collision data, we don't care about this
 860                                         // collision
 861                                         if (enterfrac2 >= trace->fraction)
 862                                                 return;
 863                                         ie = 1.0f - enterfrac;
 864                                         newimpactplane[0] = startplane[0] * ie + endplane[0] * enterfrac;
 865                                         newimpactplane[1] = startplane[1] * ie + endplane[1] * enterfrac;
 866                                         newimpactplane[2] = startplane[2] * ie + endplane[2] * enterfrac;
 867                                         newimpactplane[3] = startplane[3] * ie + endplane[3] * enterfrac;
 868                                         hitq3surfaceflags = other_start->planes[nplane].q3surfaceflags;
 869                                         hittexture = other_start->planes[nplane].texture;
 870                                 }
 871                         }
 872                 }
 873                 else
 874                 {
 875                         // moving out of brush
 876                         if (startdist > 0)
 877                                 return;
 878                         if (enddist > 0)
 879                         {
 880                                 // leave
 881                                 f = (startdist + collision_leavenudge.value) / (startdist - enddist);
 882                                 if (f > 1)
 883                                         f = 1;
 884                                 // check if this will reduce the collision time range
 885                                 if (leavefrac > f)
 886                                 {
 887                                         // reduced collision time range
 888                                         leavefrac = f;
 889                                         // if the collision time range is now empty, no collision
 890                                         if (enterfrac > leavefrac)
 891                                                 return;
 892                                 }
 893                         }
 894                 }
 895         }
 896
 897         // at this point we know the trace overlaps the brush because it was not
 898         // rejected at any point in the loop above
 899
 900         // see if the trace started outside the brush or not
 901         if (enterfrac > -1)
 902         {
 903                 // started outside, and overlaps, therefore there is a collision here
 904                 // store out the impact information
 905                 if (trace->hitsupercontentsmask & other_start->supercontents)
 906                 {
 907                         trace->hitsupercontents = other_start->supercontents;
 908                         trace->hitq3surfaceflags = hitq3surfaceflags;
 909                         trace->hittexture = hittexture;
 910                         trace->fraction = bound(0, enterfrac2, 1);
 911                         VectorCopy(newimpactplane, trace->plane.normal);
 912                         trace->plane.dist = newimpactplane[3];
 913                 }
 914         }
 915         else
 916         {
 917                 // started inside, update startsolid and friends
 918                 trace->startsupercontents |= other_start->supercontents;
 919                 if (trace->hitsupercontentsmask & other_start->supercontents)
 920                 {
 921                         trace->startsolid = true;
 922                         if (leavefrac < 1)
 923                                 trace->allsolid = true;
 924                         VectorCopy(newimpactplane, trace->plane.normal);
 925                         trace->plane.dist = newimpactplane[3];
 926                         if (trace->startdepth > startdepth)
 927                         {
 928                                 trace->startdepth = startdepth;
 929                                 VectorCopy(startdepthnormal, trace->startdepthnormal);
 930                         }
 931                 }
 932         }
 933 }
 934
 935 qboolean Collision_PointInsideBrushFloat(const vec3_t point, const colbrushf_t *brush)
 936 {
 937         int nplane;
 938         const colplanef_t *plane;
 939
 940         if (!BoxesOverlap(point, point, brush->mins, brush->maxs))
 941                 return false;
 942         for (nplane = 0, plane = brush->planes;nplane < brush->numplanes;nplane++, plane++)
 943                 if (DotProduct(plane->normal, point) > plane->dist)
 944                         return false;
 945         return true;
 946 }
 947
 948 void Collision_TracePointBrushFloat(trace_t *trace, const vec3_t point, const colbrushf_t *thatbrush)
 949 {
 950         if (!Collision_PointInsideBrushFloat(point, thatbrush))
 951                 return;
 952
 953         trace->startsupercontents |= thatbrush->supercontents;
 954         if (trace->hitsupercontentsmask & thatbrush->supercontents)
 955         {
 956                 trace->startsolid = true;
 957                 trace->allsolid = true;
 958         }
 959 }
 960
 961 static void Collision_SnapCopyPoints(int numpoints, const colpointf_t *in, colpointf_t *out, float fractionprecision, float invfractionprecision)
 962 {
 963         int i;
 964         for (i = 0;i < numpoints;i++)
 965         {
 966                 out[i].v[0] = floor(in[i].v[0] * fractionprecision + 0.5f) * invfractionprecision;
 967                 out[i].v[1] = floor(in[i].v[1] * fractionprecision + 0.5f) * invfractionprecision;
 968                 out[i].v[2] = floor(in[i].v[2] * fractionprecision + 0.5f) * invfractionprecision;
 969         }
 970 }
 971
 972 void Collision_TraceBrushTriangleMeshFloat(trace_t *trace, const colbrushf_t *thisbrush_start, const colbrushf_t *thisbrush_end, int numtriangles, const int *element3i, const float *vertex3f, int stride, float *bbox6f, int supercontents, int q3surfaceflags, const texture_t *texture, const vec3_t segmentmins, const vec3_t segmentmaxs)
 973 {
 974         int i;
 975         colpointf_t points[3];
 976         colpointf_t edgedirs[3];
 977         colplanef_t planes[5];
 978         colbrushf_t brush;
 979         memset(&brush, 0, sizeof(brush));
 980         brush.isaabb = false;
 981         brush.hasaabbplanes = false;
 982         brush.numpoints = 3;
 983         brush.numedgedirs = 3;
 984         brush.numplanes = 5;
 985         brush.points = points;
 986         brush.edgedirs = edgedirs;
 987         brush.planes = planes;
 988         brush.supercontents = supercontents;
 989         brush.q3surfaceflags = q3surfaceflags;
 990         brush.texture = texture;
 991         for (i = 0;i < brush.numplanes;i++)
 992         {
 993                 brush.planes[i].q3surfaceflags = q3surfaceflags;
 994                 brush.planes[i].texture = texture;
 995         }
 996         if(stride > 0)
 997         {
 998                 int k, cnt, tri;
 999                 cnt = (numtriangles + stride - 1) / stride;
1000                 for(i = 0; i < cnt; ++i)
1001                 {
1002                         if(BoxesOverlap(bbox6f + i * 6, bbox6f + i * 6 + 3, segmentmins, segmentmaxs))
1003                         {
1004                                 for(k = 0; k < stride; ++k)
1005                                 {
1006                                         tri = i * stride + k;
1007                                         if(tri >= numtriangles)
1008                                                 break;
1009                                         VectorCopy(vertex3f + element3i[tri * 3 + 0] * 3, points[0].v);
1010                                         VectorCopy(vertex3f + element3i[tri * 3 + 1] * 3, points[1].v);
1011                                         VectorCopy(vertex3f + element3i[tri * 3 + 2] * 3, points[2].v);
1012                                         Collision_SnapCopyPoints(brush.numpoints, points, points, COLLISION_SNAPSCALE, COLLISION_SNAP);
1013                                         Collision_CalcEdgeDirsForPolygonBrushFloat(&brush);
1014                                         Collision_CalcPlanesForTriangleBrushFloat(&brush);
1015                                         //Collision_PrintBrushAsQHull(&brush, "brush");
1016                                         Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &brush, &brush);
1017                                 }
1018                         }
1019                 }
1020         }
1021         else if(stride == 0)
1022         {
1023                 for (i = 0;i < numtriangles;i++, element3i += 3)
1024                 {
1025                         if (TriangleBBoxOverlapsBox(vertex3f + element3i[0]*3, vertex3f + element3i[1]*3, vertex3f + element3i[2]*3, segmentmins, segmentmaxs))
1026                         {
1027                                 VectorCopy(vertex3f + element3i[0] * 3, points[0].v);
1028                                 VectorCopy(vertex3f + element3i[1] * 3, points[1].v);
1029                                 VectorCopy(vertex3f + element3i[2] * 3, points[2].v);
1030                                 Collision_SnapCopyPoints(brush.numpoints, points, points, COLLISION_SNAPSCALE, COLLISION_SNAP);
1031                                 Collision_CalcEdgeDirsForPolygonBrushFloat(&brush);
1032                                 Collision_CalcPlanesForTriangleBrushFloat(&brush);
1033                                 //Collision_PrintBrushAsQHull(&brush, "brush");
1034                                 Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &brush, &brush);
1035                         }
1036                 }
1037         }
1038         else
1039         {
1040                 for (i = 0;i < numtriangles;i++, element3i += 3)
1041                 {
1042                         VectorCopy(vertex3f + element3i[0] * 3, points[0].v);
1043                         VectorCopy(vertex3f + element3i[1] * 3, points[1].v);
1044                         VectorCopy(vertex3f + element3i[2] * 3, points[2].v);
1045                         Collision_SnapCopyPoints(brush.numpoints, points, points, COLLISION_SNAPSCALE, COLLISION_SNAP);
1046                         Collision_CalcEdgeDirsForPolygonBrushFloat(&brush);
1047                         Collision_CalcPlanesForTriangleBrushFloat(&brush);
1048                         //Collision_PrintBrushAsQHull(&brush, "brush");
1049                         Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &brush, &brush);
1050                 }
1051         }
1052 }
1053
1054 void Collision_TraceLineTriangleMeshFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, int numtriangles, const int *element3i, const float *vertex3f, int stride, float *bbox6f, int supercontents, int q3surfaceflags, const texture_t *texture, const vec3_t segmentmins, const vec3_t segmentmaxs)
1055 {
1056         int i;
1057         // FIXME: snap vertices?
1058         if(stride > 0)
1059         {
1060                 int k, cnt, tri;
1061                 cnt = (numtriangles + stride - 1) / stride;
1062                 for(i = 0; i < cnt; ++i)
1063                 {
1064                         if(BoxesOverlap(bbox6f + i * 6, bbox6f + i * 6 + 3, segmentmins, segmentmaxs))
1065                         {
1066                                 for(k = 0; k < stride; ++k)
1067                                 {
1068                                         tri = i * stride + k;
1069                                         if(tri >= numtriangles)
1070                                                 break;
1071                                         Collision_TraceLineTriangleFloat(trace, linestart, lineend, vertex3f + element3i[tri * 3 + 0] * 3, vertex3f + element3i[tri * 3 + 1] * 3, vertex3f + element3i[tri * 3 + 2] * 3, supercontents, q3surfaceflags, texture);
1072                                 }
1073                         }
1074                 }
1075         }
1076         else
1077         {
1078                 for (i = 0;i < numtriangles;i++, element3i += 3)
1079                         Collision_TraceLineTriangleFloat(trace, linestart, lineend, vertex3f + element3i[0] * 3, vertex3f + element3i[1] * 3, vertex3f + element3i[2] * 3, supercontents, q3surfaceflags, texture);
1080         }
1081 }
1082
1083 void Collision_TraceBrushTriangleFloat(trace_t *trace, const colbrushf_t *thisbrush_start, const colbrushf_t *thisbrush_end, const float *v0, const float *v1, const float *v2, int supercontents, int q3surfaceflags, const texture_t *texture)
1084 {
1085         int i;
1086         colpointf_t points[3];
1087         colpointf_t edgedirs[3];
1088         colplanef_t planes[5];
1089         colbrushf_t brush;
1090         memset(&brush, 0, sizeof(brush));
1091         brush.isaabb = false;
1092         brush.hasaabbplanes = false;
1093         brush.numpoints = 3;
1094         brush.numedgedirs = 3;
1095         brush.numplanes = 5;
1096         brush.points = points;
1097         brush.edgedirs = edgedirs;
1098         brush.planes = planes;
1099         brush.supercontents = supercontents;
1100         brush.q3surfaceflags = q3surfaceflags;
1101         brush.texture = texture;
1102         for (i = 0;i < brush.numplanes;i++)
1103         {
1104                 brush.planes[i].q3surfaceflags = q3surfaceflags;
1105                 brush.planes[i].texture = texture;
1106         }
1107         VectorCopy(v0, points[0].v);
1108         VectorCopy(v1, points[1].v);
1109         VectorCopy(v2, points[2].v);
1110         Collision_SnapCopyPoints(brush.numpoints, points, points, COLLISION_SNAPSCALE, COLLISION_SNAP);
1111         Collision_CalcEdgeDirsForPolygonBrushFloat(&brush);
1112         Collision_CalcPlanesForTriangleBrushFloat(&brush);
1113         //Collision_PrintBrushAsQHull(&brush, "brush");
1114         Collision_TraceBrushBrushFloat(trace, thisbrush_start, thisbrush_end, &brush, &brush);
1115 }
1116
1117 void Collision_BrushForBox(colboxbrushf_t *boxbrush, const vec3_t mins, const vec3_t maxs, int supercontents, int q3surfaceflags, const texture_t *texture)
1118 {
1119         int i;
1120         memset(boxbrush, 0, sizeof(*boxbrush));
1121         boxbrush->brush.isaabb = true;
1122         boxbrush->brush.hasaabbplanes = true;
1123         boxbrush->brush.points = boxbrush->points;
1124         boxbrush->brush.edgedirs = boxbrush->edgedirs;
1125         boxbrush->brush.planes = boxbrush->planes;
1126         boxbrush->brush.supercontents = supercontents;
1127         boxbrush->brush.q3surfaceflags = q3surfaceflags;
1128         boxbrush->brush.texture = texture;
1129         if (VectorCompare(mins, maxs))
1130         {
1131                 // point brush
1132                 boxbrush->brush.numpoints = 1;
1133                 boxbrush->brush.numedgedirs = 0;
1134                 boxbrush->brush.numplanes = 0;
1135                 VectorCopy(mins, boxbrush->brush.points[0].v);
1136         }
1137         else
1138         {
1139                 boxbrush->brush.numpoints = 8;
1140                 boxbrush->brush.numedgedirs = 3;
1141                 boxbrush->brush.numplanes = 6;
1142                 // there are 8 points on a box
1143                 // there are 3 edgedirs on a box (both signs are tested in collision)
1144                 // there are 6 planes on a box
1145                 VectorSet(boxbrush->brush.points[0].v, mins[0], mins[1], mins[2]);
1146                 VectorSet(boxbrush->brush.points[1].v, maxs[0], mins[1], mins[2]);
1147                 VectorSet(boxbrush->brush.points[2].v, mins[0], maxs[1], mins[2]);
1148                 VectorSet(boxbrush->brush.points[3].v, maxs[0], maxs[1], mins[2]);
1149                 VectorSet(boxbrush->brush.points[4].v, mins[0], mins[1], maxs[2]);
1150                 VectorSet(boxbrush->brush.points[5].v, maxs[0], mins[1], maxs[2]);
1151                 VectorSet(boxbrush->brush.points[6].v, mins[0], maxs[1], maxs[2]);
1152                 VectorSet(boxbrush->brush.points[7].v, maxs[0], maxs[1], maxs[2]);
1153                 VectorSet(boxbrush->brush.edgedirs[0].v, 1, 0, 0);
1154                 VectorSet(boxbrush->brush.edgedirs[1].v, 0, 1, 0);
1155                 VectorSet(boxbrush->brush.edgedirs[2].v, 0, 0, 1);
1156                 VectorSet(boxbrush->brush.planes[0].normal, -1,  0,  0);boxbrush->brush.planes[0].dist = -mins[0];
1157                 VectorSet(boxbrush->brush.planes[1].normal,  1,  0,  0);boxbrush->brush.planes[1].dist =  maxs[0];
1158                 VectorSet(boxbrush->brush.planes[2].normal,  0, -1,  0);boxbrush->brush.planes[2].dist = -mins[1];
1159                 VectorSet(boxbrush->brush.planes[3].normal,  0,  1,  0);boxbrush->brush.planes[3].dist =  maxs[1];
1160                 VectorSet(boxbrush->brush.planes[4].normal,  0,  0, -1);boxbrush->brush.planes[4].dist = -mins[2];
1161                 VectorSet(boxbrush->brush.planes[5].normal,  0,  0,  1);boxbrush->brush.planes[5].dist =  maxs[2];
1162                 for (i = 0;i < 6;i++)
1163                 {
1164                         boxbrush->brush.planes[i].q3surfaceflags = q3surfaceflags;
1165                         boxbrush->brush.planes[i].texture = texture;
1166                 }
1167         }
1168         boxbrush->brush.supercontents = supercontents;
1169         boxbrush->brush.q3surfaceflags = q3surfaceflags;
1170         boxbrush->brush.texture = texture;
1171         VectorSet(boxbrush->brush.mins, mins[0] - 1, mins[1] - 1, mins[2] - 1);
1172         VectorSet(boxbrush->brush.maxs, maxs[0] + 1, maxs[1] + 1, maxs[2] + 1);
1173         //Collision_ValidateBrush(&boxbrush->brush);
1174 }
1175
1176 //pseudocode for detecting line/sphere overlap without calculating an impact point
1177 //linesphereorigin = sphereorigin - linestart;linediff = lineend - linestart;linespherefrac = DotProduct(linesphereorigin, linediff) / DotProduct(linediff, linediff);return VectorLength2(linesphereorigin - bound(0, linespherefrac, 1) * linediff) >= sphereradius*sphereradius;
1178
1179 // LordHavoc: currently unused, but tested
1180 // note: this can be used for tracing a moving sphere vs a stationary sphere,
1181 // by simply adding the moving sphere's radius to the sphereradius parameter,
1182 // all the results are correct (impactpoint, impactnormal, and fraction)
1183 float Collision_ClipTrace_Line_Sphere(double *linestart, double *lineend, double *sphereorigin, double sphereradius, double *impactpoint, double *impactnormal)
1184 {
1185         double dir[3], scale, v[3], deviationdist2, impactdist, linelength;
1186         // make sure the impactpoint and impactnormal are valid even if there is
1187         // no collision
1188         VectorCopy(lineend, impactpoint);
1189         VectorClear(impactnormal);
1190         // calculate line direction
1191         VectorSubtract(lineend, linestart, dir);
1192         // normalize direction
1193         linelength = VectorLength(dir);
1194         if (linelength)
1195         {
1196                 scale = 1.0 / linelength;
1197                 VectorScale(dir, scale, dir);
1198         }
1199         // this dotproduct calculates the distance along the line at which the
1200         // sphere origin is (nearest point to the sphere origin on the line)
1201         impactdist = DotProduct(sphereorigin, dir) - DotProduct(linestart, dir);
1202         // calculate point on line at that distance, and subtract the
1203         // sphereorigin from it, so we have a vector to measure for the distance
1204         // of the line from the sphereorigin (deviation, how off-center it is)
1205         VectorMA(linestart, impactdist, dir, v);
1206         VectorSubtract(v, sphereorigin, v);
1207         deviationdist2 = sphereradius * sphereradius - VectorLength2(v);
1208         // if squared offset length is outside the squared sphere radius, miss
1209         if (deviationdist2 < 0)
1210                 return 1; // miss (off to the side)
1211         // nudge back to find the correct impact distance
1212         impactdist -= sqrt(deviationdist2);
1213         if (impactdist >= linelength)
1214                 return 1; // miss (not close enough)
1215         if (impactdist < 0)
1216                 return 1; // miss (linestart is past or inside sphere)
1217         // calculate new impactpoint
1218         VectorMA(linestart, impactdist, dir, impactpoint);
1219         // calculate impactnormal (surface normal at point of impact)
1220         VectorSubtract(impactpoint, sphereorigin, impactnormal);
1221         // normalize impactnormal
1222         VectorNormalize(impactnormal);
1223         // return fraction of movement distance
1224         return impactdist / linelength;
1225 }
1226
1227 void Collision_TraceLineTriangleFloat(trace_t *trace, const vec3_t linestart, const vec3_t lineend, const float *point0, const float *point1, const float *point2, int supercontents, int q3surfaceflags, const texture_t *texture)
1228 {
1229         float d1, d2, d, f, f2, impact[3], edgenormal[3], faceplanenormal[3], faceplanedist, faceplanenormallength2, edge01[3], edge21[3], edge02[3];
1230
1231         // this function executes:
1232         // 32 ops when line starts behind triangle
1233         // 38 ops when line ends infront of triangle
1234         // 43 ops when line fraction is already closer than this triangle
1235         // 72 ops when line is outside edge 01
1236         // 92 ops when line is outside edge 21
1237         // 115 ops when line is outside edge 02
1238         // 123 ops when line impacts triangle and updates trace results
1239
1240         // this code is designed for clockwise triangles, conversion to
1241         // counterclockwise would require swapping some things around...
1242         // it is easier to simply swap the point0 and point2 parameters to this
1243         // function when calling it than it is to rewire the internals.
1244
1245         // calculate the faceplanenormal of the triangle, this represents the front side
1246         // 15 ops
1247         VectorSubtract(point0, point1, edge01);
1248         VectorSubtract(point2, point1, edge21);
1249         CrossProduct(edge01, edge21, faceplanenormal);
1250         // there's no point in processing a degenerate triangle (GIGO - Garbage In, Garbage Out)
1251         // 6 ops
1252         faceplanenormallength2 = DotProduct(faceplanenormal, faceplanenormal);
1253         if (faceplanenormallength2 < 0.0001f)
1254                 return;
1255         // calculate the distance
1256         // 5 ops
1257         faceplanedist = DotProduct(point0, faceplanenormal);
1258
1259         // if start point is on the back side there is no collision
1260         // (we don't care about traces going through the triangle the wrong way)
1261
1262         // calculate the start distance
1263         // 6 ops
1264         d1 = DotProduct(faceplanenormal, linestart);
1265         if (d1 <= faceplanedist)
1266                 return;
1267
1268         // calculate the end distance
1269         // 6 ops
1270         d2 = DotProduct(faceplanenormal, lineend);
1271         // if both are in front, there is no collision
1272         if (d2 >= faceplanedist)
1273                 return;
1274
1275         // from here on we know d1 is >= 0 and d2 is < 0
1276         // this means the line starts infront and ends behind, passing through it
1277
1278         // calculate the recipricol of the distance delta,
1279         // so we can use it multiple times cheaply (instead of division)
1280         // 2 ops
1281         d = 1.0f / (d1 - d2);
1282         // calculate the impact fraction by taking the start distance (> 0)
1283         // and subtracting the face plane distance (this is the distance of the
1284         // triangle along that same normal)
1285         // then multiply by the recipricol distance delta
1286         // 4 ops
1287         f = (d1 - faceplanedist) * d;
1288         f2  = f - collision_impactnudge.value * d;
1289         // skip out if this impact is further away than previous ones
1290         // 1 ops
1291         if (f2 >= trace->fraction)
1292                 return;
1293         // calculate the perfect impact point for classification of insidedness
1294         // 9 ops
1295         impact[0] = linestart[0] + f * (lineend[0] - linestart[0]);
1296         impact[1] = linestart[1] + f * (lineend[1] - linestart[1]);
1297         impact[2] = linestart[2] + f * (lineend[2] - linestart[2]);
1298
1299         // calculate the edge normal and reject if impact is outside triangle
1300         // (an edge normal faces away from the triangle, to get the desired normal
1301         //  a crossproduct with the faceplanenormal is used, and because of the way
1302         // the insidedness comparison is written it does not need to be normalized)
1303
1304         // first use the two edges from the triangle plane math
1305         // the other edge only gets calculated if the point survives that long
1306
1307         // 20 ops
1308         CrossProduct(edge01, faceplanenormal, edgenormal);
1309         if (DotProduct(impact, edgenormal) > DotProduct(point1, edgenormal))
1310                 return;
1311
1312         // 20 ops
1313         CrossProduct(faceplanenormal, edge21, edgenormal);
1314         if (DotProduct(impact, edgenormal) > DotProduct(point2, edgenormal))
1315                 return;
1316
1317         // 23 ops
1318         VectorSubtract(point0, point2, edge02);
1319         CrossProduct(faceplanenormal, edge02, edgenormal);
1320         if (DotProduct(impact, edgenormal) > DotProduct(point0, edgenormal))
1321                 return;
1322
1323         // 8 ops (rare)
1324
1325         // store the new trace fraction
1326         trace->fraction = f2;
1327
1328         // store the new trace plane (because collisions only happen from
1329         // the front this is always simply the triangle normal, never flipped)
1330         d = 1.0 / sqrt(faceplanenormallength2);
1331         VectorScale(faceplanenormal, d, trace->plane.normal);
1332         trace->plane.dist = faceplanedist * d;
1333
1334         trace->hitsupercontents = supercontents;
1335         trace->hitq3surfaceflags = q3surfaceflags;
1336         trace->hittexture = texture;
1337 }
1338
1339 void Collision_BoundingBoxOfBrushTraceSegment(const colbrushf_t *start, const colbrushf_t *end, vec3_t mins, vec3_t maxs, float startfrac, float endfrac)
1340 {
1341         int i;
1342         colpointf_t *ps, *pe;
1343         float tempstart[3], tempend[3];
1344         VectorLerp(start->points[0].v, startfrac, end->points[0].v, mins);
1345         VectorCopy(mins, maxs);
1346         for (i = 0, ps = start->points, pe = end->points;i < start->numpoints;i++, ps++, pe++)
1347         {
1348                 VectorLerp(ps->v, startfrac, pe->v, tempstart);
1349                 VectorLerp(ps->v, endfrac, pe->v, tempend);
1350                 mins[0] = min(mins[0], min(tempstart[0], tempend[0]));
1351                 mins[1] = min(mins[1], min(tempstart[1], tempend[1]));
1352                 mins[2] = min(mins[2], min(tempstart[2], tempend[2]));
1353                 maxs[0] = min(maxs[0], min(tempstart[0], tempend[0]));
1354                 maxs[1] = min(maxs[1], min(tempstart[1], tempend[1]));
1355                 maxs[2] = min(maxs[2], min(tempstart[2], tempend[2]));
1356         }
1357         mins[0] -= 1;
1358         mins[1] -= 1;
1359         mins[2] -= 1;
1360         maxs[0] += 1;
1361         maxs[1] += 1;
1362         maxs[2] += 1;
1363 }
1364
1365 //===========================================
1366
1367 static void Collision_TranslateBrush(const vec3_t shift, colbrushf_t *brush)
1368 {
1369         int i;
1370         // now we can transform the data
1371         for(i = 0; i < brush->numplanes; ++i)
1372         {
1373                 brush->planes[i].dist += DotProduct(shift, brush->planes[i].normal);
1374         }
1375         for(i = 0; i < brush->numpoints; ++i)
1376         {
1377                 VectorAdd(brush->points[i].v, shift, brush->points[i].v);
1378         }
1379         VectorAdd(brush->mins, shift, brush->mins);
1380         VectorAdd(brush->maxs, shift, brush->maxs);
1381 }
1382
1383 static void Collision_TransformBrush(const matrix4x4_t *matrix, colbrushf_t *brush)
1384 {
1385         int i;
1386         vec3_t v;
1387         // we're breaking any AABB properties here...
1388         brush->isaabb = false;
1389         brush->hasaabbplanes = false;
1390         // now we can transform the data
1391         for(i = 0; i < brush->numplanes; ++i)
1392         {
1393                 Matrix4x4_TransformPositivePlane(matrix, brush->planes[i].normal[0], brush->planes[i].normal[1], brush->planes[i].normal[2], brush->planes[i].dist, brush->planes[i].normal);
1394         }
1395         for(i = 0; i < brush->numedgedirs; ++i)
1396         {
1397                 Matrix4x4_Transform(matrix, brush->edgedirs[i].v, v);
1398                 VectorCopy(v, brush->edgedirs[i].v);
1399         }
1400         for(i = 0; i < brush->numpoints; ++i)
1401         {
1402                 Matrix4x4_Transform(matrix, brush->points[i].v, v);
1403                 VectorCopy(v, brush->points[i].v);
1404         }
1405         VectorCopy(brush->points[0].v, brush->mins);
1406         VectorCopy(brush->points[0].v, brush->maxs);
1407         for(i = 1; i < brush->numpoints; ++i)
1408         {
1409                 if(brush->points[i].v[0] < brush->mins[0]) brush->mins[0] = brush->points[i].v[0];
1410                 if(brush->points[i].v[1] < brush->mins[1]) brush->mins[1] = brush->points[i].v[1];
1411                 if(brush->points[i].v[2] < brush->mins[2]) brush->mins[2] = brush->points[i].v[2];
1412                 if(brush->points[i].v[0] > brush->maxs[0]) brush->maxs[0] = brush->points[i].v[0];
1413                 if(brush->points[i].v[1] > brush->maxs[1]) brush->maxs[1] = brush->points[i].v[1];
1414                 if(brush->points[i].v[2] > brush->maxs[2]) brush->maxs[2] = brush->points[i].v[2];
1415         }
1416 }
1417
1418 typedef struct collision_cachedtrace_parameters_s
1419 {
1420         dp_model_t *model;
1421         vec3_t end;
1422         vec3_t start;
1423         int hitsupercontentsmask;
1424         matrix4x4_t matrix;
1425 }
1426 collision_cachedtrace_parameters_t;
1427
1428 typedef struct collision_cachedtrace_s
1429 {
1430         qboolean valid;
1431         collision_cachedtrace_parameters_t p;
1432         trace_t result;
1433 }
1434 collision_cachedtrace_t;
1435
1436 static mempool_t *collision_cachedtrace_mempool;
1437 static collision_cachedtrace_t *collision_cachedtrace_array;
1438 static int collision_cachedtrace_firstfree;
1439 static int collision_cachedtrace_lastused;
1440 static int collision_cachedtrace_max;
1441 static int collision_cachedtrace_sequence;
1442 static int collision_cachedtrace_hashsize;
1443 static int *collision_cachedtrace_hash;
1444 static unsigned int *collision_cachedtrace_arrayfullhashindex;
1445 static unsigned int *collision_cachedtrace_arrayhashindex;
1446 static unsigned int *collision_cachedtrace_arraynext;
1447 static unsigned char *collision_cachedtrace_arrayused;
1448 static qboolean collision_cachedtrace_rebuildhash;
1449
1450 void Collision_Cache_Reset(qboolean resetlimits)
1451 {
1452         if (collision_cachedtrace_hash)
1453                 Mem_Free(collision_cachedtrace_hash);
1454         if (collision_cachedtrace_array)
1455                 Mem_Free(collision_cachedtrace_array);
1456         if (collision_cachedtrace_arrayfullhashindex)
1457                 Mem_Free(collision_cachedtrace_arrayfullhashindex);
1458         if (collision_cachedtrace_arrayhashindex)
1459                 Mem_Free(collision_cachedtrace_arrayhashindex);
1460         if (collision_cachedtrace_arraynext)
1461                 Mem_Free(collision_cachedtrace_arraynext);
1462         if (collision_cachedtrace_arrayused)
1463                 Mem_Free(collision_cachedtrace_arrayused);
1464         if (resetlimits || !collision_cachedtrace_max)
1465                 collision_cachedtrace_max = collision_cache.integer ? 128 : 1;
1466         collision_cachedtrace_firstfree = 1;
1467         collision_cachedtrace_lastused = 0;
1468         collision_cachedtrace_hashsize = collision_cachedtrace_max;
1469         collision_cachedtrace_array = (collision_cachedtrace_t *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_max * sizeof(collision_cachedtrace_t));
1470         collision_cachedtrace_hash = (int *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_hashsize * sizeof(int));
1471         collision_cachedtrace_arrayfullhashindex = (unsigned int *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_max * sizeof(unsigned int));
1472         collision_cachedtrace_arrayhashindex = (unsigned int *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_max * sizeof(unsigned int));
1473         collision_cachedtrace_arraynext = (unsigned int *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_max * sizeof(unsigned int));
1474         collision_cachedtrace_arrayused = (unsigned char *)Mem_Alloc(collision_cachedtrace_mempool, collision_cachedtrace_max * sizeof(unsigned char));
1475         collision_cachedtrace_sequence = 1;
1476         collision_cachedtrace_rebuildhash = false;
1477 }
1478
1479 void Collision_Cache_Init(mempool_t *mempool)
1480 {
1481         collision_cachedtrace_mempool = mempool;
1482         Collision_Cache_Reset(true);
1483 }
1484
1485 static void Collision_Cache_RebuildHash(void)
1486 {
1487         int index;
1488         int range = collision_cachedtrace_lastused + 1;
1489         int sequence = collision_cachedtrace_sequence;
1490         int firstfree = collision_cachedtrace_max;
1491         int lastused = 0;
1492         int *hash = collision_cachedtrace_hash;
1493         unsigned int hashindex;
1494         unsigned int *arrayhashindex = collision_cachedtrace_arrayhashindex;
1495         unsigned int *arraynext = collision_cachedtrace_arraynext;
1496         collision_cachedtrace_rebuildhash = false;
1497         memset(collision_cachedtrace_hash, 0, collision_cachedtrace_hashsize * sizeof(int));
1498         for (index = 1;index < range;index++)
1499         {
1500                 if (collision_cachedtrace_arrayused[index] == sequence)
1501                 {
1502                         hashindex = arrayhashindex[index];
1503                         arraynext[index] = hash[hashindex];
1504                         hash[hashindex] = index;
1505                         lastused = index;
1506                 }
1507                 else
1508                 {
1509                         if (firstfree > index)
1510                                 firstfree = index;
1511                         collision_cachedtrace_arrayused[index] = 0;
1512                 }
1513         }
1514         collision_cachedtrace_firstfree = firstfree;
1515         collision_cachedtrace_lastused = lastused;
1516 }
1517
1518 void Collision_Cache_NewFrame(void)
1519 {
1520         if (collision_cache.integer)
1521         {
1522                 if (collision_cachedtrace_max < 128)
1523                         Collision_Cache_Reset(true);
1524         }
1525         else
1526         {
1527                 if (collision_cachedtrace_max > 1)
1528                         Collision_Cache_Reset(true);
1529         }
1530         // rebuild hash if sequence would overflow byte, otherwise increment
1531         if (collision_cachedtrace_sequence == 255)
1532         {
1533                 Collision_Cache_RebuildHash();
1534                 collision_cachedtrace_sequence = 1;
1535         }
1536         else
1537         {
1538                 collision_cachedtrace_rebuildhash = true;
1539                 collision_cachedtrace_sequence++;
1540         }
1541 }
1542
1543 static unsigned int Collision_Cache_HashIndexForArray(unsigned int *array, unsigned int size)
1544 {
1545         unsigned int i;
1546         unsigned int hashindex = 0;
1547         // this is a super-cheesy checksum, designed only for speed
1548         for (i = 0;i < size;i++)
1549                 hashindex += array[i] * (1 + i);
1550         return hashindex;
1551 }
1552
1553 static collision_cachedtrace_t *Collision_Cache_Lookup(dp_model_t *model, const matrix4x4_t *matrix, const matrix4x4_t *inversematrix, const vec3_t start, const vec3_t end, int hitsupercontentsmask)
1554 {
1555         int hashindex = 0;
1556         unsigned int fullhashindex;
1557         int index = 0;
1558         int range;
1559         int sequence = collision_cachedtrace_sequence;
1560         int *hash = collision_cachedtrace_hash;
1561         unsigned int *arrayfullhashindex = collision_cachedtrace_arrayfullhashindex;
1562         unsigned int *arraynext = collision_cachedtrace_arraynext;
1563         collision_cachedtrace_t *cached = collision_cachedtrace_array + index;
1564         collision_cachedtrace_parameters_t params;
1565         // all non-cached traces use the same index
1566         if (!collision_cache.integer)
1567                 r_refdef.stats[r_stat_photoncache_traced]++;
1568         else
1569         {
1570                 // cached trace lookup
1571                 memset(&params, 0, sizeof(params));
1572                 params.model = model;
1573                 VectorCopy(start, params.start);
1574                 VectorCopy(end,   params.end);
1575                 params.hitsupercontentsmask = hitsupercontentsmask;
1576                 params.matrix = *matrix;
1577                 fullhashindex = Collision_Cache_HashIndexForArray((unsigned int *)&params, sizeof(params) / sizeof(unsigned int));
1578                 hashindex = (int)(fullhashindex % (unsigned int)collision_cachedtrace_hashsize);
1579                 for (index = hash[hashindex];index;index = arraynext[index])
1580                 {
1581                         if (arrayfullhashindex[index] != fullhashindex)
1582                                 continue;
1583                         cached = collision_cachedtrace_array + index;
1584                         //if (memcmp(&cached->p, &params, sizeof(params)))
1585                         if (cached->p.model != params.model
1586                          || cached->p.end[0] != params.end[0]
1587                          || cached->p.end[1] != params.end[1]
1588                          || cached->p.end[2] != params.end[2]
1589                          || cached->p.start[0] != params.start[0]
1590                          || cached->p.start[1] != params.start[1]
1591                          || cached->p.start[2] != params.start[2]
1592                          || cached->p.hitsupercontentsmask != params.hitsupercontentsmask
1593                          || cached->p.matrix.m[0][0] != params.matrix.m[0][0]
1594                          || cached->p.matrix.m[0][1] != params.matrix.m[0][1]
1595                          || cached->p.matrix.m[0][2] != params.matrix.m[0][2]
1596                          || cached->p.matrix.m[0][3] != params.matrix.m[0][3]
1597                          || cached->p.matrix.m[1][0] != params.matrix.m[1][0]
1598                          || cached->p.matrix.m[1][1] != params.matrix.m[1][1]
1599                          || cached->p.matrix.m[1][2] != params.matrix.m[1][2]
1600                          || cached->p.matrix.m[1][3] != params.matrix.m[1][3]
1601                          || cached->p.matrix.m[2][0] != params.matrix.m[2][0]
1602                          || cached->p.matrix.m[2][1] != params.matrix.m[2][1]
1603                          || cached->p.matrix.m[2][2] != params.matrix.m[2][2]
1604                          || cached->p.matrix.m[2][3] != params.matrix.m[2][3]
1605                          || cached->p.matrix.m[3][0] != params.matrix.m[3][0]
1606                          || cached->p.matrix.m[3][1] != params.matrix.m[3][1]
1607                          || cached->p.matrix.m[3][2] != params.matrix.m[3][2]
1608                          || cached->p.matrix.m[3][3] != params.matrix.m[3][3]
1609                         )
1610                                 continue;
1611                         // found a matching trace in the cache
1612                         r_refdef.stats[r_stat_photoncache_cached]++;
1613                         cached->valid = true;
1614                         collision_cachedtrace_arrayused[index] = collision_cachedtrace_sequence;
1615                         return cached;
1616                 }
1617                 r_refdef.stats[r_stat_photoncache_traced]++;
1618                 // find an unused cache entry
1619                 for (index = collision_cachedtrace_firstfree, range = collision_cachedtrace_max;index < range;index++)
1620                         if (collision_cachedtrace_arrayused[index] == 0)
1621                                 break;
1622                 if (index == range)
1623                 {
1624                         // all claimed, but probably some are stale...
1625                         for (index = 1, range = collision_cachedtrace_max;index < range;index++)
1626                                 if (collision_cachedtrace_arrayused[index] != sequence)
1627                                         break;
1628                         if (index < range)
1629                         {
1630                                 // found a stale one, rebuild the hash
1631                                 Collision_Cache_RebuildHash();
1632                         }
1633                         else
1634                         {
1635                                 // we need to grow the cache
1636                                 collision_cachedtrace_max *= 2;
1637                                 Collision_Cache_Reset(false);
1638                                 index = 1;
1639                         }
1640                 }
1641                 // link the new cache entry into the hash bucket
1642                 collision_cachedtrace_firstfree = index + 1;
1643                 if (collision_cachedtrace_lastused < index)
1644                         collision_cachedtrace_lastused = index;
1645                 cached = collision_cachedtrace_array + index;
1646                 collision_cachedtrace_arraynext[index] = collision_cachedtrace_hash[hashindex];
1647                 collision_cachedtrace_hash[hashindex] = index;
1648                 collision_cachedtrace_arrayhashindex[index] = hashindex;
1649                 cached->valid = false;
1650                 cached->p = params;
1651                 collision_cachedtrace_arrayfullhashindex[index] = fullhashindex;
1652                 collision_cachedtrace_arrayused[index] = collision_cachedtrace_sequence;
1653         }
1654         return cached;
1655 }
1656
1657 void Collision_Cache_ClipLineToGenericEntitySurfaces(trace_t *trace, dp_model_t *model, matrix4x4_t *matrix, matrix4x4_t *inversematrix, const vec3_t start, const vec3_t end, int hitsupercontentsmask)
1658 {
1659         collision_cachedtrace_t *cached = Collision_Cache_Lookup(model, matrix, inversematrix, start, end, hitsupercontentsmask);
1660         if (cached->valid)
1661         {
1662                 *trace = cached->result;
1663                 return;
1664         }
1665
1666         Collision_ClipLineToGenericEntity(trace, model, NULL, NULL, vec3_origin, vec3_origin, 0, matrix, inversematrix, start, end, hitsupercontentsmask, collision_extendmovelength.value, true);
1667
1668         cached->result = *trace;
1669 }
1670
1671 void Collision_Cache_ClipLineToWorldSurfaces(trace_t *trace, dp_model_t *model, const vec3_t start, const vec3_t end, int hitsupercontents)
1672 {
1673         collision_cachedtrace_t *cached = Collision_Cache_Lookup(model, &identitymatrix, &identitymatrix, start, end, hitsupercontents);
1674         if (cached->valid)
1675         {
1676                 *trace = cached->result;
1677                 return;
1678         }
1679
1680         Collision_ClipLineToWorld(trace, model, start, end, hitsupercontents, collision_extendmovelength.value, true);
1681
1682         cached->result = *trace;
1683 }
1684
1685 typedef struct extendtraceinfo_s
1686 {
1687         trace_t *trace;
1688         float realstart[3];
1689         float realend[3];
1690         float realdelta[3];
1691         float extendstart[3];
1692         float extendend[3];
1693         float extenddelta[3];
1694         float reallength;
1695         float extendlength;
1696         float scaletoextend;
1697         float extend;
1698 }
1699 extendtraceinfo_t;
1700
1701 static void Collision_ClipExtendPrepare(extendtraceinfo_t *extendtraceinfo, trace_t *trace, const vec3_t tstart, const vec3_t tend, float textend)
1702 {
1703         memset(trace, 0, sizeof(*trace));
1704         trace->fraction = 1;
1705
1706         extendtraceinfo->trace = trace;
1707         VectorCopy(tstart, extendtraceinfo->realstart);
1708         VectorCopy(tend, extendtraceinfo->realend);
1709         VectorSubtract(extendtraceinfo->realend, extendtraceinfo->realstart, extendtraceinfo->realdelta);
1710         VectorCopy(extendtraceinfo->realstart, extendtraceinfo->extendstart);
1711         VectorCopy(extendtraceinfo->realend, extendtraceinfo->extendend);
1712         VectorCopy(extendtraceinfo->realdelta, extendtraceinfo->extenddelta);
1713         extendtraceinfo->reallength = VectorLength(extendtraceinfo->realdelta);
1714         extendtraceinfo->extendlength = extendtraceinfo->reallength;
1715         extendtraceinfo->scaletoextend = 1.0f;
1716         extendtraceinfo->extend = textend;
1717
1718         // make the trace longer according to the extend parameter
1719         if (extendtraceinfo->reallength && extendtraceinfo->extend)
1720         {
1721                 extendtraceinfo->extendlength = extendtraceinfo->reallength + extendtraceinfo->extend;
1722                 extendtraceinfo->scaletoextend = extendtraceinfo->extendlength / extendtraceinfo->reallength;
1723                 VectorMA(extendtraceinfo->realstart, extendtraceinfo->scaletoextend, extendtraceinfo->realdelta, extendtraceinfo->extendend);
1724                 VectorSubtract(extendtraceinfo->extendend, extendtraceinfo->extendstart, extendtraceinfo->extenddelta);
1725         }
1726 }
1727
1728 static void Collision_ClipExtendFinish(extendtraceinfo_t *extendtraceinfo)
1729 {
1730         trace_t *trace = extendtraceinfo->trace;
1731
1732         if (trace->fraction != 1.0f)
1733         {
1734                 // undo the extended trace length
1735                 trace->fraction *= extendtraceinfo->scaletoextend;
1736
1737                 // if the extended trace hit something that the unextended trace did not hit (even considering the collision_impactnudge), then we have to clear the hit information
1738                 if (trace->fraction > 1.0f)
1739                 {
1740                         // note that ent may refer to either startsolid or fraction<1, we can't restore the startsolid ent unfortunately
1741                         trace->ent = NULL;
1742                         trace->hitq3surfaceflags = 0;
1743                         trace->hitsupercontents = 0;
1744                         trace->hittexture = NULL;
1745                         VectorClear(trace->plane.normal);
1746                         trace->plane.dist = 0.0f;
1747                 }
1748         }
1749
1750         // clamp things
1751         trace->fraction = bound(0, trace->fraction, 1);
1752
1753         // calculate the end position
1754         VectorMA(extendtraceinfo->realstart, trace->fraction, extendtraceinfo->realdelta, trace->endpos);
1755 }
1756
1757 void Collision_ClipToGenericEntity(trace_t *trace, dp_model_t *model, const frameblend_t *frameblend, const skeleton_t *skeleton, const vec3_t bodymins, const vec3_t bodymaxs, int bodysupercontents, matrix4x4_t *matrix, matrix4x4_t *inversematrix, const vec3_t tstart, const vec3_t mins, const vec3_t maxs, const vec3_t tend, int hitsupercontentsmask, float extend)
1758 {
1759         vec3_t starttransformed, endtransformed;
1760         extendtraceinfo_t extendtraceinfo;
1761         Collision_ClipExtendPrepare(&extendtraceinfo, trace, tstart, tend, extend);
1762
1763         Matrix4x4_Transform(inversematrix, extendtraceinfo.extendstart, starttransformed);
1764         Matrix4x4_Transform(inversematrix, extendtraceinfo.extendend, endtransformed);
1765 #if COLLISIONPARANOID >= 3
1766         Con_Printf("trans(%f %f %f -> %f %f %f, %f %f %f -> %f %f %f)", extendtraceinfo.extendstart[0], extendtraceinfo.extendstart[1], extendtraceinfo.extendstart[2], starttransformed[0], starttransformed[1], starttransformed[2], extendtraceinfo.extendend[0], extendtraceinfo.extendend[1], extendtraceinfo.extendend[2], endtransformed[0], endtransformed[1], endtransformed[2]);
1767 #endif
1768
1769         if (model && model->TraceBox)
1770         {
1771                 if(model->TraceBrush && (inversematrix->m[0][1] || inversematrix->m[0][2] || inversematrix->m[1][0] || inversematrix->m[1][2] || inversematrix->m[2][0] || inversematrix->m[2][1]))
1772                 {
1773                         // we get here if TraceBrush exists, AND we have a rotation component (SOLID_BSP case)
1774                         // using starttransformed, endtransformed is WRONG in this case!
1775                         // should rather build a brush and trace using it
1776                         colboxbrushf_t thisbrush_start, thisbrush_end;
1777                         Collision_BrushForBox(&thisbrush_start, mins, maxs, 0, 0, NULL);
1778                         Collision_BrushForBox(&thisbrush_end, mins, maxs, 0, 0, NULL);
1779                         Collision_TranslateBrush(extendtraceinfo.extendstart, &thisbrush_start.brush);
1780                         Collision_TranslateBrush(extendtraceinfo.extendend, &thisbrush_end.brush);
1781                         Collision_TransformBrush(inversematrix, &thisbrush_start.brush);
1782                         Collision_TransformBrush(inversematrix, &thisbrush_end.brush);
1783                         //Collision_TranslateBrush(starttransformed, &thisbrush_start.brush);
1784                         //Collision_TranslateBrush(endtransformed, &thisbrush_end.brush);
1785                         model->TraceBrush(model, frameblend, skeleton, trace, &thisbrush_start.brush, &thisbrush_end.brush, hitsupercontentsmask);
1786                 }
1787                 else // this is only approximate if rotated, quite useless
1788                         model->TraceBox(model, frameblend, skeleton, trace, starttransformed, mins, maxs, endtransformed, hitsupercontentsmask);
1789         }
1790         else // and this requires that the transformation matrix doesn't have angles components, like SV_TraceBox ensures; FIXME may get called if a model is SOLID_BSP but has no TraceBox function
1791                 Collision_ClipTrace_Box(trace, bodymins, bodymaxs, starttransformed, mins, maxs, endtransformed, hitsupercontentsmask, bodysupercontents, 0, NULL);
1792
1793         Collision_ClipExtendFinish(&extendtraceinfo);
1794
1795         // transform plane
1796         // NOTE: this relies on plane.dist being directly after plane.normal
1797         Matrix4x4_TransformPositivePlane(matrix, trace->plane.normal[0], trace->plane.normal[1], trace->plane.normal[2], trace->plane.dist, trace->plane.normal);
1798 }
1799
1800 void Collision_ClipToWorld(trace_t *trace, dp_model_t *model, const vec3_t tstart, const vec3_t mins, const vec3_t maxs, const vec3_t tend, int hitsupercontents, float extend)
1801 {
1802         extendtraceinfo_t extendtraceinfo;
1803         Collision_ClipExtendPrepare(&extendtraceinfo, trace, tstart, tend, extend);
1804         // ->TraceBox: TraceBrush not needed here, as worldmodel is never rotated
1805         if (model && model->TraceBox)
1806                 model->TraceBox(model, NULL, NULL, trace, extendtraceinfo.extendstart, mins, maxs, extendtraceinfo.extendend, hitsupercontents);
1807         Collision_ClipExtendFinish(&extendtraceinfo);
1808 }
1809
1810 void Collision_ClipLineToGenericEntity(trace_t *trace, dp_model_t *model, const frameblend_t *frameblend, const skeleton_t *skeleton, const vec3_t bodymins, const vec3_t bodymaxs, int bodysupercontents, matrix4x4_t *matrix, matrix4x4_t *inversematrix, const vec3_t tstart, const vec3_t tend, int hitsupercontentsmask, float extend, qboolean hitsurfaces)
1811 {
1812         vec3_t starttransformed, endtransformed;
1813         extendtraceinfo_t extendtraceinfo;
1814         Collision_ClipExtendPrepare(&extendtraceinfo, trace, tstart, tend, extend);
1815
1816         Matrix4x4_Transform(inversematrix, extendtraceinfo.extendstart, starttransformed);
1817         Matrix4x4_Transform(inversematrix, extendtraceinfo.extendend, endtransformed);
1818 #if COLLISIONPARANOID >= 3
1819         Con_Printf("trans(%f %f %f -> %f %f %f, %f %f %f -> %f %f %f)", extendtraceinfo.extendstart[0], extendtraceinfo.extendstart[1], extendtraceinfo.extendstart[2], starttransformed[0], starttransformed[1], starttransformed[2], extendtraceinfo.extendend[0], extendtraceinfo.extendend[1], extendtraceinfo.extendend[2], endtransformed[0], endtransformed[1], endtransformed[2]);
1820 #endif
1821
1822         if (model && model->TraceLineAgainstSurfaces && hitsurfaces)
1823                 model->TraceLineAgainstSurfaces(model, frameblend, skeleton, trace, starttransformed, endtransformed, hitsupercontentsmask);
1824         else if (model && model->TraceLine)
1825                 model->TraceLine(model, frameblend, skeleton, trace, starttransformed, endtransformed, hitsupercontentsmask);
1826         else
1827                 Collision_ClipTrace_Box(trace, bodymins, bodymaxs, starttransformed, vec3_origin, vec3_origin, endtransformed, hitsupercontentsmask, bodysupercontents, 0, NULL);
1828
1829         Collision_ClipExtendFinish(&extendtraceinfo);
1830
1831         // transform plane
1832         // NOTE: this relies on plane.dist being directly after plane.normal
1833         Matrix4x4_TransformPositivePlane(matrix, trace->plane.normal[0], trace->plane.normal[1], trace->plane.normal[2], trace->plane.dist, trace->plane.normal);
1834 }
1835
1836 void Collision_ClipLineToWorld(trace_t *trace, dp_model_t *model, const vec3_t tstart, const vec3_t tend, int hitsupercontents, float extend, qboolean hitsurfaces)
1837 {
1838         extendtraceinfo_t extendtraceinfo;
1839         Collision_ClipExtendPrepare(&extendtraceinfo, trace, tstart, tend, extend);
1840
1841         if (model && model->TraceLineAgainstSurfaces && hitsurfaces)
1842                 model->TraceLineAgainstSurfaces(model, NULL, NULL, trace, extendtraceinfo.extendstart, extendtraceinfo.extendend, hitsupercontents);
1843         else if (model && model->TraceLine)
1844                 model->TraceLine(model, NULL, NULL, trace, extendtraceinfo.extendstart, extendtraceinfo.extendend, hitsupercontents);
1845
1846         Collision_ClipExtendFinish(&extendtraceinfo);
1847 }
1848
1849 void Collision_ClipPointToGenericEntity(trace_t *trace, dp_model_t *model, const frameblend_t *frameblend, const skeleton_t *skeleton, const vec3_t bodymins, const vec3_t bodymaxs, int bodysupercontents, matrix4x4_t *matrix, matrix4x4_t *inversematrix, const vec3_t start, int hitsupercontentsmask)
1850 {
1851         float starttransformed[3];
1852         memset(trace, 0, sizeof(*trace));
1853         trace->fraction = 1;
1854
1855         Matrix4x4_Transform(inversematrix, start, starttransformed);
1856 #if COLLISIONPARANOID >= 3
1857         Con_Printf("trans(%f %f %f -> %f %f %f)", start[0], start[1], start[2], starttransformed[0], starttransformed[1], starttransformed[2]);
1858 #endif
1859
1860         if (model && model->TracePoint)
1861                 model->TracePoint(model, NULL, NULL, trace, starttransformed, hitsupercontentsmask);
1862         else
1863                 Collision_ClipTrace_Point(trace, bodymins, bodymaxs, starttransformed, hitsupercontentsmask, bodysupercontents, 0, NULL);
1864
1865         VectorCopy(start, trace->endpos);
1866         // transform plane
1867         // NOTE: this relies on plane.dist being directly after plane.normal
1868         Matrix4x4_TransformPositivePlane(matrix, trace->plane.normal[0], trace->plane.normal[1], trace->plane.normal[2], trace->plane.dist, trace->plane.normal);
1869 }
1870
1871 void Collision_ClipPointToWorld(trace_t *trace, dp_model_t *model, const vec3_t start, int hitsupercontents)
1872 {
1873         memset(trace, 0, sizeof(*trace));
1874         trace->fraction = 1;
1875         if (model && model->TracePoint)
1876                 model->TracePoint(model, NULL, NULL, trace, start, hitsupercontents);
1877         VectorCopy(start, trace->endpos);
1878 }
1879
1880 void Collision_CombineTraces(trace_t *cliptrace, const trace_t *trace, void *touch, qboolean isbmodel)
1881 {
1882         // take the 'best' answers from the new trace and combine with existing data
1883         if (trace->allsolid)
1884                 cliptrace->allsolid = true;
1885         if (trace->startsolid)
1886         {
1887                 if (isbmodel)
1888                         cliptrace->bmodelstartsolid = true;
1889                 cliptrace->startsolid = true;
1890                 if (cliptrace->fraction == 1)
1891                         cliptrace->ent = touch;
1892                 if (cliptrace->startdepth > trace->startdepth)
1893                 {
1894                         cliptrace->startdepth = trace->startdepth;
1895                         VectorCopy(trace->startdepthnormal, cliptrace->startdepthnormal);
1896                 }
1897         }
1898         // don't set this except on the world, because it can easily confuse
1899         // monsters underwater if there's a bmodel involved in the trace
1900         // (inopen && inwater is how they check water visibility)
1901         //if (trace->inopen)
1902         //      cliptrace->inopen = true;
1903         if (trace->inwater)
1904                 cliptrace->inwater = true;
1905         if ((trace->fraction < cliptrace->fraction) && (VectorLength2(trace->plane.normal) > 0))
1906         {
1907                 cliptrace->fraction = trace->fraction;
1908                 VectorCopy(trace->endpos, cliptrace->endpos);
1909                 cliptrace->plane = trace->plane;
1910                 cliptrace->ent = touch;
1911                 cliptrace->hitsupercontents = trace->hitsupercontents;
1912                 cliptrace->hitq3surfaceflags = trace->hitq3surfaceflags;
1913                 cliptrace->hittexture = trace->hittexture;
1914         }
1915         cliptrace->startsupercontents |= trace->startsupercontents;
1916 }